[When should patients with aortic valve stenosis be surgically treated?]. / Cuándo operar a los enfermos con estenosis de la válvula aórtica?

Optimal time for choosing Aortic Valve Replacement in Aortic Stenosis patients is based on understanding the natural history of the disease and prognostic variables, such as age, symptom status and co-morbid factors. In patients with advanced congestive heart failure, the valvular area and transvalvular gradients, determined by echocardiography and cardiac catheterization studies, have limitations for preoperative evaluation; before surgery the reversibility of this myocardial depression must be identified. At present, there is widespread agreement that valve replacement is indicated for symptomatic severe aortic stenosis regardless of age; however, cardiac surgery remains controversial in asymptomatic patients but with abnormal response to exercise, ventricular tachycardia, valve area lesser than 0.6 cm2, and marked or excessive left ventricular hypertrophy. The presence of moderate or severe valvular calcification, together with a rapid increase in aortic-jet velocity, identifies patients with a very poor prognosis and these patients should be considered for surgery. Finally, the decision to operate a patient must be considered on individual factors and whether quality of life is improved, and not just on operative mortality and morbidity.

[Late thrombolysis and electrical stability in acute myocardial infarction. Role of the collateral flow]. / Trombolisis tardía y estabilidad eléctrica en el infarto agudo del miocardio: importancia del flujo colateral.

We evaluated 249 patients (pts) with first acute myocardial infarction: 1. Pts without thrombolysis, n = 119, 2. Pts treated with thrombolysis within 6 hours following MI, n = 80 and 3. Pts treated with thrombolysis between 6-12 hours after MI. Arrhythmic events were evaluated during follow up. All underwent heart rate variability studies and coronary angiogram where anterograde flow (TIMI) and collateral flow (Rentrop scale 0-2 = poor collateral flow and 3 = good collateral flow) were determined. Pts in group 2 and 3 showed a better anterograde and collateral flow than group 1 (p < 0.001). A lower spectral power in the high frequency band and a higher ratio low/high frequency band were observed in group 1 (p < 0.05). Conjunctive consolidation analysis showed more malignant arrhythmias in TIMI 0-2 with poor collateral flow than TIMI 0-2 with good collateral flow (17/138-12.3% vs 0/14-0%). Kaplan Meier analysis was able to demonstrate more cardiac sudden death events in TIMI 0-2 with poor collateral flow than TIMI 0-2 with good collateral flow or TIMI 3 (x2 = 7.22, p = 0.028), independently of thrombolytic treatment.